Improvement in compositions for artificial stone



106. con osmnns,

COATING on PLASTIC 92 Cross Reference UNITED STATES PATENT OFFICE.

I combines wit FRANCIS COLBY AND ED\VIN EVASS, OF STREATOR, ILLINOIS.

lMPROVEMENT IN COMPOSlTlONS FOR ARTIFICIAL'STONE.

Specification forming part of Letters Patent No. 157.312., datedDecember 1, 1874; application filed May 16, 1874. 1

expel no lo urination. 0 silicate of lime, or

illuminate oi'lime, or both silicate and alumi-,

nnt-c oi lime, or coihpoundsot' silica, lime, and almnina, and toincrease the quantity oi'.silicute of lime or aluminate of lime, or ofboth, in a given mass of materials for making stone,

and to render said mass more plastic, thereby improving its handling andmolding quali ties. We add to the aqueous saccharine solution thedesired quantity of a soluble silicate, and call the combination thecombining-solvent. r

Most artificial stones owe their hardness, strength, and durabilityprincipally to the compounds of silica. and alumina which enter intotheir composition.

Lime is soluble in seven hundred parts of cold water. It is much moresoluble in sir-ups an d aqueous saccharine solutions.

When silicates in solution are added to a mortaro Iatime e imeinsolution promptly 1e silica in the silicates, t'orining the silicate oflime. The greater the quantity of dissolved lime the more silicate oflime will be formed. The more silicate of lime formed the harder willthe mass become.

Now, when the mortar is made with a saccharine solution it contains muchmore dissolved lime than when made with water. Hence, more silicate oflime is formed, and the mass becomes a stone, as combination,evaporation, and crystallization progress.

Hvdranlic lime contains silicate of lime as tic resu 0 ca cinatiou.\Vhen Water is added more silicate of lime is formed by the transfer ofsoluble lime .to the silica, which has not combined under the influenceof heat. The silicate formed during calcination also becomes hydrated.

com Bmations.

These hydrosilicates soon crystallize or set, hardening the mass. Thehardness is increased by increasing the amount of silicate of lime. Thisis-done by moistening the mass with the combining-solvent instead ofwater.

Result, hard stone.

Hydraulic cements all contain various proportions of silicates of lime,aluminates of lime,

free alumina, 850., their compounds varying with the intensity of thecalcining heat.

All these compounds set after becoming hydrated, forming a hardinsoluble compound. The hardness is intensified by increasing the amountof silicate and alnminate of lime,

which is done by adding a small proportion of lime-powder to the cement,moistening the whole with the combining-solvent, and tho?- oughlymixing.

The combiniiw-solvent resents lime in so lution to the free silica andaluminaof the cement thus facilitating and expediting their It alsodissolves lime in immediatocontact with the added silicate, thusinsuring a transfer of lime to the silica. The anhydrous silicatesformed during calcination are at the same time hydrated.

The ultimate result of the combinations facilitated and produced by thisprocess is a superior stone, of great hardness, strength, anddurability.

e is smoother and more plastic when a little lime and accharine matterare added, than when made with water and cement alone. After the properamount of sand is added to cement-paste so made, the mass handlesbetter, (is less choppy,) molds better, makes a more perfect cast, andcomes out of the molds smoother than when only cemcut, water, and sandare used, and the stones are less porous than when made in the usualway.

Four quarts of limeowder to one bushel of cement is a; proportion thatmeets all the reqm-rements in the manufacture of our stone.

The combining-solventis made by dissolu ing in four gallons of m say,two pounds 0% sugar or siru or mo asses and two pounds 0 silicate 0 soa,'or s; mate of otash or siligate of soda and potash, tor Port landcemeiiT's;

four ponn l icate for common Eytxamine.

dranlie cgmgnas; and four and one-fourth] pounds for {at nnes.

mg, substantially as specified.

FRANCIS W. COLBY.

We call our stone Prairie Granite.

EDWIN EVANS.

We claim as our invention The plastic composition for producing anVVit-nesses: tificial stone, consisting of hydraulic cement, SAM. J.JOHNSON, lime-powder, sugar, silicate of soda, sand, and A. OSBORN.

gravel, thoroughly mixed together before mold

